Re: [PATCH 7/7] vp_vdpa: report doorbell address

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:47AM -0400, Jason Wang wrote:
> This patch reports the per vq doorbell location and size to vDPA
> bus. Userspace can then map the doorbell via mmap() via vhost-vDPA bus
> driver.
> 
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>

Reviewed-by: Eli Cohen <elic@xxxxxxxxxx>

> ---
>  drivers/vdpa/virtio_pci/vp_vdpa.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
> index 98205e54d089..002b928d0ca1 100644
> --- a/drivers/vdpa/virtio_pci/vp_vdpa.c
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
> @@ -26,6 +26,7 @@ struct vp_vring {
>  	void __iomem *notify;
>  	char msix_name[VP_VDPA_NAME_SIZE];
>  	struct vdpa_callback cb;
> +	resource_size_t notify_pa;
>  	int irq;
>  };
>  
> @@ -336,6 +337,19 @@ static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa,
>  	vp_vdpa->config_cb = *cb;
>  }
>  
> +static struct vdpa_notification_area
> +vp_vdpa_get_vq_notification(struct vdpa_device *vdpa, u16 qid)
> +{
> +	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> +	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
> +	struct vdpa_notification_area notify;
> +
> +	notify.addr = vp_vdpa->vring[qid].notify_pa;
> +	notify.size = mdev->notify_offset_multiplier;
> +
> +	return notify;
> +}
> +
>  static const struct vdpa_config_ops vp_vdpa_ops = {
>  	.get_features	= vp_vdpa_get_features,
>  	.set_features	= vp_vdpa_set_features,
> @@ -343,6 +357,7 @@ static const struct vdpa_config_ops vp_vdpa_ops = {
>  	.set_status	= vp_vdpa_set_status,
>  	.get_vq_num_max	= vp_vdpa_get_vq_num_max,
>  	.get_vq_state	= vp_vdpa_get_vq_state,
> +	.get_vq_notification = vp_vdpa_get_vq_notification,
>  	.set_vq_state	= vp_vdpa_set_vq_state,
>  	.set_vq_cb	= vp_vdpa_set_vq_cb,
>  	.set_vq_ready	= vp_vdpa_set_vq_ready,
> @@ -416,7 +431,8 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  	for (i = 0; i < vp_vdpa->queues; i++) {
>  		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
>  		vp_vdpa->vring[i].notify =
> -			vp_modern_map_vq_notify(mdev, i, NULL);
> +			vp_modern_map_vq_notify(mdev, i,
> +						&vp_vdpa->vring[i].notify_pa);
>  		if (!vp_vdpa->vring[i].notify) {
>  			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
>  			goto err;
> -- 
> 2.18.1
>